Winding for single-phase induction-motors.



No. 896,217. PATENTED AUG. 18,1908.

F. R. KUNKEL. WINDING FOR SINGLE PHASE 'INDUGTION MOTORS.

APPLIGATION FILED DEO.3, 1906.

- WITNESSES;

. i N.- Mwm CI! 6. BY

I 7 ATTORNEY Unrran a ias rannr OFFICE.

FRED 1t. K'JNREL, F EDGEWOOD PXRK, PENNSYLVANIA, ASSIGNOR WESTINGHOUSEELl KTltlO it M)NUFACTPRING COMPANY, A CORPORATION OF PENNSYLVANIA.

WZNDING FOR SINGLE-PHASE INDUCTION-MOTORS;

No.{896,2 17. Specification 01'.

Letters Patent. Patented Aug. 18, 1908.

Application filed December 3, 1906. Serial No. 346,080.

To all whom it may concern:

Be it known that I, l nen R. KUNKEL, a citizeirof the United States, anda resident of Edgewood Park, in the. county of Allegheny and State ofPem'isylvania, have invented a new and nseful Improvement in i Vindingsfor Single-Phase Inductionitlotors, of which the following'is aspecification.

My invention relates to windings for dynamo-electric machines, andparticularly to the primary windings of'sir1gle.-}')l\ase inductionmotor a The object ol my invention is to provide a w nding that shallpermit of the application of either of two voltages to a nwtor having anauxiliary winding to aid in starting.

For the purpose oi all'ording a starting torque for single-phaseinduction motors, auxiliary windings having dilierent time constantsfrom theme in windings are frequently com iected in parallel relationtothe main windings until the motors attain predetermined speeds. Suchmotors may be adapted for operation by either of two voltages bydividing the main winding into two sections that may be arrai'iged .inseries relation for the higher voltage amlin parallel relation for thelower voltage and, when so adapted, I propose to conncct theauxiliaryc-r starting winding in parallel relation to one section onlyof the main winding, in order that the same voltage may always beapplied thereto. I propose, further, to so arrange the sections of themain winding that the fluxes produced thereby may be so interlinked asto make the resultant lield flux approximately the same for all portionsof the magnetic circuit.

Figure 1 of the accompanying drawing is a diagrammatic view of thewinding of a motor that embodies my inventibn, and Fig. 2 a simi ar viewof a modification of a portion of what is shown in Fig. 1. v

Referring to Fig. 1 the main 'wii'iding of an induction motor is dividedinto two sections the first of which comprises a plurality of divisionsor groups cl coils 1, 2 and 3, that are connected in series relationbetween the terminal pieces or binding posts 5 and (S, and the second ofwhich comprises a plurahiv ol" division's or groups of coils 7, 8 and S)that are connected in series relation between binding posts 10 and 11.The division or groups of coils of the rcspective sections alternate inposition in order that the fluxes produced thereby may be interlinked.For operation of the motor on a low v0ltage,the sections of the windingmay be connected in-parallel relation by means of connections 12 and 13,respectively, between the binding posts 5 and 10, and 6 and 11, and foroperation upon a high voltage the sections of the winding may beconnected in series relation by means of a 10, as indicated in Fig. 2.The motor is also ing comprising a plurality of divisions or alternatein position with the groups of coils of the main winding, and arepreierably so placed that the electrical angle between their polecenters and the pole centers of the coils of the main winding isapproximately ninety degrees, though the arrangement may be such as toprovide a smaller electrical angle if found necessary or advisable. Aresistance 21 may be connected in series withthe auxiliary winding, inorder to cause it' to have a dil'lerent time constant from that of themain winding, though other suitable means may be employed for thepurpose. The auxiliary winding is normally connected'in parallelrelation to the section of the main winding comprising divisions 1, 2and 3 by means of a switch 22 that is preferably operated by centrifugalforce when the mo tor attains a predetermined speed. As the auxiliarywinding is connected in parallel relation to one section only of themain winding, substantially the same voltage will be applied theretoregardless of' whether the motor is connected to a high or to alow vol-.tagc circuit, n'oviding, of course, that the high voltage is double thelow voltage. When two sections of the main winding are arranged inseries relation, the current which traverses the sectiont'hat is shuntedby the auxiliary winding will be less in amount than that whichtraverses the other section, and in order to overcome anynonuniformityin the ilux per pole that might result from this cause thedivisions or groups of coils of thc respective sections of the mainwinding are disposed alternately so that the fluxes produccd thereby maybe interlinked produced by with a main winding having twosectionsprovided with an auxiliary or starting wind.

groups of coils 15, 16, 17, 18, 19 and th t m such a manner as toproduce a resultant line 14 which connects binding posts 6 andalternating in position, and means for connecting the sections in eitherseries or arallel' relation, of an auxiliary winding an means forconnecting the same in parallel relation with only one section ofthemain winding when the sections are connected in series with eachother.

3. In an electric motor, the combination with a main winding having twosections adapted to be connected in either series or parallel relation,the sections being so disposed as to cause interlinking of the fluxesproduced thereby, of an auxiliary winding adapted to be connected inparallel relation with only one section of the main winding when thesections are connected in series with each other.

4. In an electric motor, the combination with a main winding com risingtwo sections adapted to be connectec in either series or parallelrelation and severally composed of a plurality of groups of coils sodisposed that the groups of one section alternate with those of theother, of an auxiliary winding comprising groups of coils which aresymmetrically disposed with reference to the groups of the main windingsections and are connected in series with each other and in parallelwith one of the sections of the main Winding.

5. In an electric motor, the combination with a main winding comprisingtwo sections adapted to be connected in either series or arallelrelation and severally composed of a plurality ofgroups of coils sodisposed that the groups of one section alternate with those of theother, of an auxiliary winding compris ing groups of coils which aresymmetrically disposed with reference to the groups of the main windingsections and are connected in series with each other and in parallelwith only one of the sections of the main winding -when the sections areconnected in series with each other.

In testimony whereof, I have hereunto subscribed my name this 28th dayof November, 1906.

FRED R. KUNKEL.

